MACRONUTRIENTS ABSORPTION AND DRY MATTER ACCUMULATION IN MAIZE

Abstract

This work aimed to evaluate dry matter (DM) and nutrient accumulation in the aerial parts of corn plants as a function of the phenological stages of plant development, using one hybrid with high grain yield potential (P 30F33) and another with high DM production potential (GNZ 2004). The randomized block design was used, in a split plot scheme with four replications, with the two hybrids as plots and eleven phenological stages of the culture as sub-plots. Maize cultivars accumulate dry matter, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, zinc and copper until near physiological plant maturity when the maximum accumulation is reached. Nutrients accumulation in the aerial parts occurred in the decreasing order: N > K > P > Ca > Mg > S > Zn > Mn > Cu > B. The nutrient absorption curves for GNZ 2004 and P 30F33 hybrids showed patterns similar to those observed in other works. The total amounts of nutrients required to produce one ton of corn grains were: 22.3 and 27.7 kg of N; 5.3 and 5.8 kg of P; 21.3 and 23.2 kg of K; 3.6 and 3.9 kg of Ca; 2.4 and 3.5 kg of Mg; 1.3 and 1.9 kg of S, respectively for the hybrids P 30F33 and GNZ 2004. The maximum DM accumulation in leaves and straws was obtained at phenological stage 6, and in stems, corn cobs and grains at stages 9 and 10 of plant development.

Keywords

• Zea mays
• nutrients accumulation
• hybrid maize
• fertilization